I've just moved from Chrome back to Firefox because I really like nightly version 57.0. I've installed both nightly versions in desktop and Android and setup my Firefox Sync account. In the desktop build everything works fine but the Android app is not syncyng my passwords. The bookmarks and the other synced stuff is present in my Android phone.

I searched in Firefox support and the only thing I found was because of the presence of master password in Firefox for Android which I don't have.I thought that, maybe, it wasn't still implemented in Firefox for Android build because it's in active development so I installed both Firefox for Android stable and BETA but the problem persists in both cases.

Has anyone any idea why the passwords are not being synced in my phone?